Microbiology Chapters 20,21,22

Microorganisms Prokaryotes Bacteria Eukaryotes Protists Fungus Viruses Nonliving or Living?

Viruses Living because they reproduce Nonliving because… Sizes: This is what we consider them to be in this class! Living because they reproduce Nonliving because… Require a host aka Parasitic Replicate instead of reproduce Sizes: Smaller than monerans (Bacteria) Almost all organisms have one virus that infects them. They are “host-specific” meaning that they will usually only infect 1 organism.

Viral Parts Capsid: outer protein coat Genetic Material: DNA or RNA Envelope: Protective layer around the capsid. NOT ALL VIRUSES HAVE THESE Comes from the host cell membrane

Viral Shapes Spiral, polygons, rods, bullet, needle Bacteriophage

Types of Viruses Bacteriophages Infect Bacteria only

Types of Viruses DNA Viruses Has DNA as Genetic Material Double-stranded DNA virus: Chicken pox (Varicella zoster) Single-stranded DNA virus: Canine Parvovirus

DNA Viruses Herpes Virus in a host cell Adenovirus: causes some colds Human Papilloma virus: causes warts

Has RNA as Genetic Material RNA viruses Rhinovirus: Common Cold Has RNA as Genetic Material Paramyxovirus: Measles and Mumps (in a host cell) Rabies virus

Types of Viruses Retroviruses- RNA as genetic material. To replicate, they convert RNA to DNA and then use host to make more RNA. HIV (Human immunodeficiency virus)

Characteristics of Bacteria (Monerans) All are prokaryotic All have a cell wall All have DNA as genetic material All have ribosomes, and no other organelles All are unicellular Most are heterotrophic (not all!), some are chemo or photo-autotrophic

Shapes Coccus: Round bacteria Example: Staphylococcus sp.

Shapes Bacillus: rod bacteria Example: Bacillus anthracis

Shapes Spirochetes: spiral bacteria Example: Treponema pallidum

Fungus Characteristics Eukaryotes Heterotrophic decomposers Saprophytes, parasites, predators, mutualistic Non-motile

Cell walls of chitin Most have hyphae that into tangled masses called mycelium Growth occurs rapidly at tips

General Characteristics of Protists Have a nucleus Are grouped based on the method of locomotion Cilia Flagella Pseudopods Non-motile

3 Groups Protozoans animals Algae plants Molds fungus

Microorganism benefits Viral Cystic fibrosis treatment Tulip colors Treat bacterial diseases *** Genetic engineering *** Bacteria Fix nitrogen Decomposer Food production Sewage treatment Antibiotics Genetic engineering Fungus Mutualism Fermentation Protists Producers in water Oxygen production

Microorganism disadvantages Viral Disease Cancer Bacteria Spoilage Fungus Protists Algal blooms

What do microorganisms need? Each species has an OPTIMUM Temperature pH Air Osmotic Pressure Water Nutrients

How can we prevent them from getting these requirements? Heat Change pH Add salt or sugar Remove oxygen (canning) Remove water by Dehydrating foods

How do we spread diseases and how do we stop them? Five methods for spreading disease. AIR FOOD WATER PERSON to PERSON VECTORS- insects

How does an infection makes us sick? What they do: Grow and Reproduce Destroys cells Release toxins Block passages What we do: Crummy Article

Germ Theory of Disease 1857 Louis Pasteur Eliminates theory of spontaneous generation Saves the wine Industry in France Proposes that there is a relationship between a microorganism (pathogen) and a disease Develops Pasteurization Vaccines for anthrax and rabbies

Koch’s Postulates 1876 Find suspect organism Isolate suspect and grow in pure culture Inject pure culture into healthy subject and get the same disease symptoms Re-isolate the same suspect organism and grow it in pure culture

Vaccines: Treatment for viruses Taken as a preventative method Cannot help you once you have the disease Viruses can become resistant to these, but it is not usually a fast process Human production Antibiotics: Treatment for bacterial infections Taken once you have the disease Cannot be used as a preventative Bacteria can easily become resistant to these Bacteria and some fungi produce these

Vaccines Involves your immune system being stimulated Dead or weakened antigen (foreign particle) Engulfing cells and antibody producing cells destroy the antigen Memory cells prepare for another infection Response to virus is faster and stronger the second time Adds to the health of the community

Antibiotics Work ONLY on bacteria Bacteria are prokaryotic, we are eukaryotic Bacteria have a cell wall, we do not. These help, but our immune system still has to “clean-up” Examples: Penicillin – stops cell wall formation Tetracycline – stops protein synthesis Ciprofloxacin – stops DNA replication

Proper use of antibiotics Prevents Resistance Only taking them for bacterial infections Taking pills on time Taking all your prescription

Time in Days Concentration Concentration of antibiotic - Effective concentration of antibiotic --- Concentration of bacteria …… Concentration of Bacteria at which you feel better ===== Concentration Shot of Penicillin-Pill taking intervals – missed interval Time in Days

Antibiotic Resistance Development of Resistance Alter the antibiotic Alter the target or structure Pump out the antibiotic Developing new anti-resistance antibiotics Target the mechanism that confers resistance Stop alteration of antibiotic Stop alteration of target Stop the molecular pumping mechanism

Stop the Spread of antibiotic resistance Do not demand antibiotics Take them exactly as prescribed Wash fruits and vegetables(no such thing) thoroughly; avoid raw eggs and undercooked meat, especially in ground form Use soaps and other products with antibacterial chemicals only when protecting a sick person whose defenses are weakened

The BIG picture Diet Rest Exercise both aerobic and resistance Personal Cleanliness e.g. wash your hands Proper Preparation and storage of food It Must Have Been Something You Ate Environmental Cleanliness pollution, filth Annual Physical

Big Picture cont… Report symptoms promptly to a responsible person Follow physicians instructions antibiotics Vaccinations: Vital The Vaccine Conundrum